In the field of industrial automation technology power switches and here especially low-voltage power switches are built into a switching cabinet via a receiving module and ultimately coupled to a primary circuit of a system to be monitored. Here a receiving module, also termed a withdrawable module or withdrawable frame in everyday parlance, is built into a switching cabinet. The receiving module built into a switching cabinet is connected electrically-conductively to the primary circuit to be monitored of the system to be monitored, so that the primary circuit of the system to be monitored is routed via primary circuit mating contact elements of the receiving module.
Thus the receiving module built into a switching cabinet is electrically-conductively connected to the circuit to be monitored (preferably a primary circuit) of the system and forms with the primary circuit mating contact element(s) the contact point for the power switch, so that the circuit of the system can be monitored by means of the power switch.
A power switch can now be mechanically coupled to the receiving module, so that the circuit to be monitored can be monitored by the power switch. In the coupled state of the power switch with the receiving module the primary circuit contact elements of the power switch are connected electrically-conductively to the primary circuit mating contact elements of the receiving module. The power switch thus establishes an electrically-conductive connection to the circuit of a system to be monitored. A system to be monitored can typically be an electrical machine.
The power switch is usually coupled to the receiving module by way of plug-in technology or push-in technology. With push-in technology the power switch is usually mechanically coupled to the receiving module via a crank. In the mechanical coupling of the power switch to the receiving module the primary circuit contact element of the power switch is thus not initially connected electrically-conductively to the primary circuit mating contact element of the receiving module. Only through the mechanical coupling step will the primary circuit contact element be connected electrically-conductively to the primary circuit mating contact element.
The power switch can have a connection unit via which a power switch accessory module can be connected to the power switch. By way of such a power switch accessory module different additional functions can be undertaken, such as diagnostic functions for example. The switch accessory module connected to a power switch is connected here by means of a single wire connection to an evaluation unit. This evaluation unit communicates with the power switch accessory module via the single wire connection.